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Question
Due to the space charge in a diode valve, _____________ .
Options
the plate current decreases
the plate voltage increases
the rate of emission of thermions increases
the saturation current increases
Solution
the plate current decreases
A diode valve consists of a negatively-charged region between the cathode and anode, called the space charge region. This negatively-charged region repels the electrons coming from the cathode and, thus, it reduces the plate current. On the other hand, this region has no effect on plate voltage, rate of emission of thermions and the saturation current.
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